This invention relates in general to techniques of identifying an individual by means of the unique pattern of ridges and valleys that are approximated by a fingerprint.
It has been recognized in the art that the pattern of line endings and line bifurcations in each of the finger ridges or valleys provide a unique set of what are called minutia. The pattern of the type of minutia, location of minutia and angular orientation of minutia is unique for each finger. An image of the surface of the finger can be provided on a flat plane, that image can be scanned in order to identify each minutia being scanned. Electronic techniques for doing this are complex and expensive. The finger image can be scanned and electronically processed to provide an identification of each minutia as to type of minutia, position in the finger image and angular orientations of minutia. As a practical matter, the costs of doing so are too prohibitive for all but in the rarest applications.
Accordingly, it is a major purpose of this invention to provide an inexpensive, simple and reliable technique for accurately identifying the minutia of a finger image.
It is important that the technique provide a minumum error rate in identification. Complex identification electronics tends to produce occasional erratic results which increase the identification error rate. Accordingly, another purpose of this invention is to provide a technique that is sufficiently reliable so that the error rate is minimal.
From the point of view of both costs and convenience it is important that the speed with which a finger or finger image being scanned is processed to provide the minutia identifying elements be as fast as possible. Accordingly, it is important that any simple, inexpensive and reliable technique meet at least the electronic processing speeds.